We have introduced a quasi–one-dimensional (1D) bosonic gas of indirect excitons in semiconductor nanotubes of type-II quantum wells and studied theoretically the coherent properties of this interacting gas. We firstly obtain the spectrum of a single exciton in such cylindrical geometry. Thus, we calculate the exciton-exciton interaction at the ground state and show that the excitons form a quasi-1D bosonic gas with repulsion interaction. Finally, by mapping the exciton gas onto an exactly solvable quasi-1D bosonic gas at the low temperature and low density limit where the bosonic features of the gas are dominant, we show that the gas is in the strong-coupling regime, and the excitons become fermions.